Question: Account for the delicate shades of colour sometimes seen on the inside of an oyster shell. State and explain the appearance presented when a beam of light falls upon a sheet of glass on which very fine equi-distant parallel lines have been scratched very close to one another.Answer: The delicate shades are due to putrefaction; the colours always show best when the oyster has been a bad one. Hence they are considered a defect and are called chromatic aberration.The scratches on the glass will arrange themselves in rings round the light, as any one may see at night in a tram car.

I am very fond of the oyster shell. It is humble and awkward and ugly. It is slate-colored and unsymmetrical. Its form is not primarily beautiful but functional. I make fun of its knobbiness. Sometimes I resent its burdens and excrescences. But its tireless adaptability and tenacity draw my astonished admiration and sometimes even my tears. And it is comfortable in its familiarity, its homeliness, like old garden gloves when have molded themselves perfectly to the shape of the hand.

In the Choice of Things, neglect not any, tho the most ordinary and trivial; the Commonest Peble or Flint, Cockle or Oyster-shell, Grass, Moss, Fern or Thistle, will be as useful, and as proper to be gathered and sent, as any the rarest production of the Country. Only take care to choose of each the fairest of its kind, and such as are perfect or whole.

Man begins life as an ambiguous speck of matter which can in no way be distinguished from the original form of the lowest animal or plant. He next becomes a cell; his life is precisely that of the animalcule. Cells cluster round this primordial cell, and the man is so far advanced that he might be mistaken for an undeveloped oyster; he grows still more, and it is clear that he might even be a fish; he then passes into a stage which is common to all quadrupeds, and next assumes a form which can only belong to quadrupeds of the higher type. At last the hour of birth approaches; coiled within the dark womb he sits, the image of an ape; a caricature of the man that is to be. He is born, and for some time he walks only on all fours; he utters only inarticulate sounds; and even in his boyhood his fondness for climbing trees would seem to be a relic of the old arboreal life.

Often referred to as osteoporosis of the ocean, [ocean acidification] prevents shell building creatures such as lobster, oyster, crab, shrimp, and coral from extracting the calcium carbonate from the water that they need to build their shells and are thus unable to survive.

The idea that we shall be welcomed as new members into the galactic community is as unlikely as the idea that the oyster will be welcomed as a new member into the human community. We're probably not even edible.

The Reproductions of the living EnsFrom sires to sons, unknown to sex, commence...Unknown to sex the pregnant oyster swells,And coral-insects build their radiate shells...Birth after birth the line unchanging runs,And fathers live transmitted in their sons;Each passing year beholds the unvarying kinds,The same their manners, and the same their minds.

What makes philosophy so tedious is not the profundity of philosophers, but their lack of art; they are like physicians who sought to cure a slight hyperacidity by prescribing a carload of burned oyster-shells.

Why are the bones of great fishes, and oysters and corals and various other shells and sea-snails, found on the high tops of mountains that border the sea, in the same way in which they are found in the depths of the sea?

In science it often happens that scientists say, 'You know that's a really good argument; my position is mistaken,' and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion.
(1987) -- Carl Sagan